Between 90 and 95% of all U.S. children have at least one documented middle ear effusion by the age 2 [1, 2]. An estimated 20 million physician visits per year in the United States are attributed to otitis media (“OM” or middle ear infections) [3, 4]. OM is by definition inflammation of the middle ear, regardless of etiology or pathogenesis. Different forms of OM are most often differentiated by the presence of fluid (effusion) and by the duration or persistence of inflammation.
Present treatment of ear infections consists of systemic oral antibiotics, a treatment which requires multiple doses over 5-10 days and systemic exposure to antibiotics. The rise in antibiotic resistance, coupled with the many multifactorial etiology of OM pose difficulties in diagnosis and treatment of OM. Furthermore, current treatment presents a number of drawbacks including patient compliance issues due to gastrointestinal side effects, lack of effective drug concentration at the site of infection, and potential for opportunistic infections. Even after acute sign subside, generally within 72 hours, the root cause of the infection may persist for the remainder of the treatment, and beyond, even up to 2 months. Thus, making compliance with a physician's prescription important to prevent reoccurrence of infection.
Recurrence of disease is striking, with one third of all children in the U.S. having 6 or more episodes of AOM by age 7 [5]. Moreover, epidemiological studies suggest that the prevalence of recurrent OM among children, particularly infants, is on the rise [6]. Around the globe, the incidence of OM in children of other industrialized nations is similar to that in the U.S. In less developed countries, however, OM remains a significant cause of childhood mortality due to late-presenting intracranial complications.
The tympanic membrane is a barrier to the direct treatment of middle ear infections. Despite being thinnest layer of skin, it is still a barrier to trans-tympanic membrane diffusion. Therefore, the direct treatment of middle ear infections is problematic. The shortcomings of the current treatment of ear diseases such as middle ear infections suggest the need for a new treatment which is noninvasive, but also direct acting.